Streetscapes/The Convent of the Sacred Heart; A Matter of Reconciling Preservation With Patina

By CHRISTOPHER GRAY

Published: February 27, 1994

YOU don't use a power sander to grind down your 18th century highboy to make it "like new," for the patina of age is as much a part of the object's beauty as the intrinsic design.

So at the old Otto Kahn mansion at the northeast corner of 91st Street and Fifth Avenue, now the Convent of the Sacred Heart, the board of the independent girls' school run in the Roman Catholic tradition is caught in its effort to preserve the building between a desire to save the patina and the knowledge that it is destroying the building.

The builder of the Italian Renaissance-style mansion came to this country from Germany in 1893, began work with the banking house of Speyer & Company and became a partner at Kuhn, Loeb & Company in 1897. His skill with railroad issues helped Kuhn, Loeb develop as a leading investment bank and he became one of the richest men in New York.

In 1913, Kahn bought the mansion's site from Andrew Carnegie, whose mansion on the other side of 91st Street is now the Cooper-Hewitt Museum. He completed his house in 1918 and moved in with his wife, Addie, four children and 22 servants.

The house, which was designed by C. P. H. Gilbert and J. Armstrong Stenhouse, was the last great mansion to rise on Fifth Avenue. Although it looks like a giant box, the rear of the building is cut to open up a deep winding courtyard that penetrates almost to the middle of the building.

This unusual feature brings light deep into the Kahn house and animates what otherwise might have been a succession of airless but magnificent interiors.

The rear yards of most mansions were mere light shafts, but the Kahn house courtyard is fully developed, all in stone, with half-stairways and small arcades of windows.

Kahn, who came from a banking family, had an appreciation of art from an early age. As a teenager he wrote a blank-verse tragedy in five acts.

By the early 1900's he was an influential figure in the arts in New York. He supported or helped many individual artists and small organizations and at his death in 1934 The New York Times wrote that he had "saved" the Metropolitan Opera.

Beginning in 1903 Kahn pumped money and talent into the Met, then an old-line institution strangling on tradition. He hired Arturo Toscanini as conductor and Giulio Gatti-Casazza as manager and even bought a site for a new opera house, on 57th Street west of Eighth Avenue, although it was never built. He was named chairman of the Met in 1911.

Rene Gimpel, in his "Diary of an Art Dealer," published in 1966, recorded a different perspective: "With so much money at his disposal, Otto Kahn resolved to storm the gates of the Four Hundred, a tremendous undertaking in this fiercely anti-Semitic society; so he invaded their sanctum, the opera [ and ] bought up its shares."

ACCORDING to "Our Crowd," Stephen Birmingham's book on Jewish families in New York, Kahn joined the opera board when Jacob Schiff, another Kuhn, Loeb partner, declined an invitation to join but suggested that the seat go to Kahn. Birmingham also says that Kahn had been planning to convert to Roman Catholicism in the early 1930's, but chose to remain a Jew out of solidarity after Hitler's rise to power.

Perhaps because of his artistic interests, Kahn brought a distinct grace to banking, and often cited ten golden rules of success, which included, "Be a good sport. Remember, you can't lift yourself by drowning others," and, "Meet your fellow-man frankly and fairly. You don't have to go through business armed to the teeth."

When Kahn died in 1934 the Convent of the Sacred Heart acquired the building from the family in exchange for the school's three old brownstones on the corner of 54th Street and Madison Avenue. Few changes have been made to the onetime mansion.

Now the school, with an enrollment of 518 girls from pre-K through 12th grade, is getting bid documents ready for a complete overhaul of the exterior stonework. The facade, of French limestone, has an exquisite, soft translucence, and is deeply pitted. The cornice is richly colored by age: deep black soot, streaks of green from copper runoff, and the soft tan of the limestone.

THE architectural firm of Buttrick, White and Burtis, of Manhattan, is supervising the project and Harold Buttrick, a partner, says that this year the school will spend $1.3 million to repair the deep pits, cut new blocks and gently clean the original stone. He says that the stone is too soft and reacts with New York's acidic air, causing large sections to disintegrate.

The testing and diagnosis of the stone problems was carried out by Building Conservation Associates. Rayond Pepi, the firm's president, said that the program would attempt to steer a middle course between esthetics and engineering.

The conventional goal would be to replace the stone or at least fill most of the holes. But, Mr. Pepi said "the pitting makes it look ancient, like a real Renaissance palazzo."

"We don't want to change the way people look at the building," he said. "What we don't do will be as important as what we do."

Photos: Otto Kahn mansion at Fifth Avenue and 91st Street, circa 1918. Exterior stonework now needs restoration. (Museum of The City of New York); Part of interior courtyard. (Avery Library); Otto Kahn in 1896. (Museum of The City of New York)